our son has been bullied for two years both physical and mental and we has to rush to emergency for head injury that happened on school property

he has come home with bruises all over his back, multiple glasses were broke, his money stolen as well as his books we bought at book fair and today we had to rush to school because same kid picked him up and slammed him into metal on bus splitting his head and had to get staples. we have reported these actions for two years and always brushed off. my son is 6 and weighs 44 pounds and is blind without his glasses and they have it on video showing this incident and how this other boy which is 3 times my son size and is alot older just grabbed my son and did this for no apparent reason. we cannot afford to hire out of pocket but will pay if someone will please help.